Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an i...Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an important phytohormone involving in plant stress.However,underlying molecular mechanisms of JA modulated osmotic stress response remains unclear.In this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea plant.Integrated transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,respectively.Suppression of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea plant.Overexpression of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol stress.Together,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant.展开更多
Harvested Prunus persica fruits cv. Dajiubao and cv. Bayuecui were immersed in 0, 0 1 or 0 3 g·L -1 salicylic acid (SA) solutions for 15 minutes,then stored at room temperatures (22～25 ℃) for 14 days or low tem...Harvested Prunus persica fruits cv. Dajiubao and cv. Bayuecui were immersed in 0, 0 1 or 0 3 g·L -1 salicylic acid (SA) solutions for 15 minutes,then stored at room temperatures (22～25 ℃) for 14 days or low temperatures (0～2 ℃) for 30 days. The results showed that after SA treatment,the activity of lipoxygenase (LOX) was inhibited significantly,contents of malondialdehyde (MDA) in the fruits also decreased.The immersion of fruit in the solutions of SA was helpful for maintaining the flesh firmness.The cell membrane electrolyte leakages of SA treated fruits,compared with control,were high during early days and low at the subsequent days.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.32202542 and U20A2045)the Project of Major Science and Technology in Anhui Province(Grant No.202003a06020021)+2 种基金the Project of Science and Technology of Yunnan Province(Grant No.202102AE090038)Anhui Provincial Natural Science Foundation(Grant No.2108085QC121)the Natural Science Projects for Colleges and Universities in the Anhui Province(Grant No.KJ2021A0145)。
文摘Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an important phytohormone involving in plant stress.However,underlying molecular mechanisms of JA modulated osmotic stress response remains unclear.In this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea plant.Integrated transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,respectively.Suppression of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea plant.Overexpression of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol stress.Together,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant.
文摘Harvested Prunus persica fruits cv. Dajiubao and cv. Bayuecui were immersed in 0, 0 1 or 0 3 g·L -1 salicylic acid (SA) solutions for 15 minutes,then stored at room temperatures (22～25 ℃) for 14 days or low temperatures (0～2 ℃) for 30 days. The results showed that after SA treatment,the activity of lipoxygenase (LOX) was inhibited significantly,contents of malondialdehyde (MDA) in the fruits also decreased.The immersion of fruit in the solutions of SA was helpful for maintaining the flesh firmness.The cell membrane electrolyte leakages of SA treated fruits,compared with control,were high during early days and low at the subsequent days.
